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Biology subjects

Liao, I. T.

Publications and source records attributed to Liao, I. T..

3 recordsLinked to original sources

Different orthology inference algorithms generate similar predicted orthogroups among Brassicaceae species

O_LIPremise - Orthology inference is crucial for comparative genomics, and multiple algorithms have been developed to identify putative orthologs for downstream analyses. Despite the abundance of proposed solutions, including publicly available benchmarks, it is difficult to assess which tool to best use for plant species, which commonly have complex genomic histories. C_LIO_LIMethods - We explored the performance of four orthology inference algorithms - OrthoFinder, SonicParanoid, Broccoli, and OrthNet - on eight Brassicaceae genomes in two groups: one group comprising only diploids and another set comprising the diploids, two mesopolyploids, and one recent hexaploid genome. C_LIO_LIResults - Orthogroup compositions reflect the species ploidy and genomic histories. Additionally, the diploid set had a higher proportion of identical orthogroups. While the diploid+higher ploidy set had a lower proportion of orthogroups with identical compositions, the average degree of similarity between the orthogroups was not different from the diploid set. C_LIO_LIDiscussion - Three algorithms - OrthoFinder, SonicParanoid, and Broccoli - are helpful for initial orthology predictions. Results from OrthNet were generally an outlier but could provide detailed information about gene colinearity. With our Brassicaceae dataset, slight discrepancies were found across the orthology inference algorithms, necessitating additional analyses, such as tree inference to fine-tune results. C_LI

genomics↗

A dicer-like3 protein affects paramutation at multiple loci in Zea mays

Paramutation is a process by which meiotically-heritable gene regulation is altered by trans-homolog interactions. In Zea mays, genetic screens for functions maintaining paramutation-induced repressed states have identified loci encoding small RNA biogenesis components, thus implicating small RNAs in mediating these trans-homolog communications. Here we report that the required to maintain repression5 locus encodes the sole dicer-like3 protein responsible for non-anther-specific 24-nucleotide RNA production. We found dicer-like3 is essential for mediating paramutation at the booster1 locus and for the meiotic maintenance of transcriptionally repressed states at the purple plant1 locus. Despite an expected role in mediating RNA-directed DNA methylation, we found 5-methylcytosine levels largely unchanged at multiple repetitive sequences in dicer-like3 mutants, with minimal compensation from other small RNA sizes. The minor effects on plant heights and flowering time seen in the absence of dicer-like3 contrasts with other paramutation mutants and we highlight one specific allele repressed by RNA polymerase IV yet unaffected by dicer-like3 loss. These findings highlight diverse regulatory functions for individual components of 24-nucleotide biogenesis occurring in the grasses and support a working model in which this small RNA size class mediates trans-homolog interactions that drive meiotically-heritable changes in gene regulation.

genetics↗

Modularity and selection of nectar traits in the evolution of the selfing syndrome in Ipomoea lacunosa (Convolvulaceae)

O_LIAlthough the evolution of the selfing syndrome often involves reductions in floral size, pollen, and nectar, few studies of selfing syndrome divergence have examined nectar. We investigate whether nectar traits have evolved independently of other floral size traits in the selfing syndrome, whether nectar traits diverged due to drift or selection, and the extent to which quantitative trait locus (QTL) analyses predict genetic correlations. C_LIO_LIWe use F5 recombinant inbred lines (RILs) generated from a cross between Ipomoea cordatotriloba and I. lacunosa. We calculate genetic correlations to identify evolutionary modules, test whether traits have been under selection, identify QTLs, and perform correlation analyses to evaluate how well QTL properties reflect the genetic correlations. C_LIO_LINectar and floral size traits form separate genetic clusters. Directional selection has acted to reduce nectar traits in the selfing I. lacunosa. Calculations from QTL properties are consistent with observed genetic correlations. C_LIO_LIFloral trait divergence during mating system syndrome evolution reflects independent evolution of at least two evolutionary modules: nectar and floral size traits. This independence implies that adaptive change in these modules requires direct selection on both floral size and nectar traits. Our study also supports the expected mechanistic link between QTL properties and genetic correlations. C_LI

evolutionary biology↗